<template>
  <div class="swiper-container" ref="imgList">
    <div class="swiper-wrapper">
      <div
        class="swiper-slide"
        v-for="(img, index) in skuImageList"
        :key="img.id"
      >
        <img @click="changeIndex(index)" :src="img.imgUrl" :class="{ active: defaultIndex === index }" />
      </div>
    </div>
    <div class="swiper-button-next"></div>
    <div class="swiper-button-prev"></div>
  </div>
</template>

<script>
import Swiper from "swiper";
export default {
  name: "ImageList",
  props: ["skuImageList"],
  data() {
    return {
      defaultIndex: 0, //参考值
    };
  },
  methods:{
    // 小图点击
    changeIndex(index){
      // 点击的这个小图需要增加上边框的样式
      this.defaultIndex = index
      // 还需要更改中图和大图 涉及到传递下标 而他们两者是兄弟 所以采用全局事件总线
      this.$bus.$emit('changeIndex',index)
    }
  },
  // 监视的数据要改变成遍历轮播图结构的数据
  // ref需要自己增加 并且获取时也要使用这个名字
  watch: {
    skuImageList: {
      handler(newVal, oldVal) {
        if(!newVal.length){
          return
        }
        this.$nextTick(() => {
          new Swiper(this.$refs.imgList, {
            slidesPerView:3, //一屏显示多少张
            slidesPerGroup:2,  //一次移动走多少张
            navigation: {
              nextEl: ".swiper-button-next",
              prevEl: ".swiper-button-prev",
            },
          });
        });
      },
      immediate:true
    },
  },
};
</script>

<style lang="less" scoped>
.swiper-container {
  height: 56px;
  width: 412px;
  box-sizing: border-box;
  padding: 0 12px;

  .swiper-slide {
    width: 56px;
    height: 56px;

    img {
      width: 100%;
      height: 100%;
      border: 1px solid #ccc;
      padding: 2px;
      width: 50px;
      height: 50px;
      display: block;

      &.active {
        border: 2px solid #f60;
        padding: 1px;
      }

      // &:hover {
      //   border: 2px solid #f60;
      //   padding: 1px;
      // }
    }
  }

  .swiper-button-next {
    left: auto;
    right: 0;
  }

  .swiper-button-prev {
    left: 0;
    right: auto;
  }

  .swiper-button-next,
  .swiper-button-prev {
    box-sizing: border-box;
    width: 12px;
    height: 56px;
    background: rgb(235, 235, 235);
    border: 1px solid rgb(204, 204, 204);
    top: 0;
    margin-top: 0;
    &::after {
      font-size: 12px;
    }
  }
}
</style>
